Surgical instruments with rotation stop devices and related methods

ABSTRACT

Surgical instruments with rotation stop devices and related methods are disclosed herein, e.g., for providing limited rotation between first and second components of the surgical instrument in a range greater than 360 degrees. Exemplary rotation stop devices can have a low profile and can include various features to facilitate packaging of the device within a larger instrument.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and is a division of U.S. patentapplication Ser. No. 15/946,016, filed Apr. 5, 2018, which is herebyincorporated by reference in its entirety.

FIELD

Surgical instruments with rotation stop devices and related methods aredisclosed herein, e.g., for providing limited rotation between first andsecond components of the surgical instrument in a range greater than 360degrees.

BACKGROUND

There are many instances in which it may be desirable to limit thedegree to which first and second components can rotate relative to oneanother. For example, in a surgical instrument having a knob rotatablerelative to a handle to manipulate a distal end of the surgicalinstrument, it may be desirable to limit the degree to which the knobcan rotate relative to the handle. A rotation limit may be desired toavoid breaking or stressing wires, optical fibers, or other componentsthat are twisted or bent during rotation. Existing approaches tolimiting rotation generally involve fixed mechanical stops disposed atdiscrete angular positions about the rotation axis, providing a limitedrotation range of less than 360 degrees. In some applications, limitedrotation between first and second components in a range greater than 360degrees may be desired. Existing approaches to limiting rotation mayalso be relatively large and difficult to package within an instrumentor device.

There is a need for improved rotation stop devices and related methods.

SUMMARY

Surgical instruments with rotation stop devices and related methods aredisclosed herein, e.g., for providing limited rotation between first andsecond components of the surgical instrument in a range greater than 360degrees. Exemplary rotation stop devices can have a low profile and caninclude various features to facilitate packaging of the device within alarger instrument.

In some embodiments, a surgical instrument can include a proximalhandle; a shaft extending from the handle and having a distally-mountedvisualization device; a knob configured to rotate relative to the handleabout a rotation axis to move the visualization device; and a rotationstop that limits rotation of the knob relative to the handle to a rangegreater than 360 degrees.

The instrument can include a sensor configured to detect a rotationalposition of the knob and to correct an electronic display of imagescaptured by the visualization device based on the detected position. Therotation stop can include a threaded shaft mated to a threaded nut, thethreaded shaft being configured to rotate with the knob and the nutbeing non-rotatably captured by the handle. The instrument can include apotentiometer having a shaft coupled to or formed integrally with thethreaded shaft. The rotation stop device can include a threaded shaftconfigured to rotate with the knob and a nut having an opening in whichthe threaded shaft is received, the nut being non-rotatably coupled tothe handle. The nut can travel along the threaded shaft between firstand second rotation limits to limit rotation of the knob relative to thehandle about the rotation axis. The first rotation limit can be asurface of the knob that faces the handle. The second rotation limit canbe a surface of the handle that faces the knob. The distance between thefirst and second rotation limits can remain constant as the knob isrotated relative to the handle. The distance between the first andsecond rotation limits can be less than or equal to 10 mm. Theinstrument can include a throughhole that extends through the knob andthe threaded shaft. The nut and the threaded shaft can be receivedwithin a cavity of the handle. The instrument can include an elongatemember that crosses a rotation plane defined between the knob and thehandle, the elongate member having a first end fixed to a portion of theinstrument distal to the rotation plane and a second end fixed to aportion of the instrument proximal to the rotation plane. The elongatemember can include an optical fiber, the first end of the elongatemember can be coupled to a light source proximal to the rotation plane,and the second end of the elongate member can be configured to directlight into a surgical field adjacent the visualization device. Theelongate member can include an electrical conductor, the first end ofthe elongate member can be coupled to a controller disposed proximal tothe rotation plane, and the second end of the elongate member can becoupled to the visualization device. The elongate member can extendthrough a throughhole of the rotation stop. The throughhole can beformed in a threaded shaft of the rotation stop.

In some embodiments, a rotation stop device can include a firstcomponent; a second component, the second component being configured torotate relative to the first component about a rotation axis; a shaftextending from the first component along the rotation axis; and a nuthaving an opening in which the shaft is received, the nut beingnon-rotatably coupled to the second component; wherein the nut travelsalong the shaft between first and second rotation limits to limitrotation of the first component relative to the second component aboutthe rotation axis.

The first and second rotation limits can limit rotation of the firstcomponent relative to the second component about the rotation axis to arange greater than 360 degrees. The first rotation limit can be asurface of the first component that faces the second component. Thesecond rotation limit can be a surface of the second component thatfaces the first component. The distance between the first and secondrotation limits can remain constant as the first component is rotatedrelative to the second component. The distance between the first andsecond rotation limits can be less than or equal to 10 mm. The devicecan include a throughhole that extends through the first component andthe shaft. The throughhole can extend through the second component. Thefirst component can be retained to the second component by one or morespring tabs that extend from the second component and through thethroughhole. The device can include a potentiometer having a shaftreceived within the throughhole. The nut and the shaft can be receivedwithin a cavity of the second component. The nut can include an innerthread mated to an outer thread of the shaft. The nut can include a pinthat rides within a helical groove of the shaft. The device can includea sensor that detects a relative rotational position of the first andsecond components. The sensor can be at least one of a potentiometer, aHall effect sensor, and an optical encoder.

In some embodiments, a surgical method can include inserting aninstrument having a camera at a distal end thereof into a patient;rotating a first portion of the instrument relative to a second portionof the instrument to adjust a position of the camera, wherein saidrotation is limited to a range greater than 360 degrees by a rotationstop; detecting a rotational position of the first portion relative tothe second portion; and adjusting an electronic display of imagescaptured by the camera based on the detected rotational position.

The first portion can include a knob and the second portion can includea handle, the knob being rotatable relative to the handle to rotate thecamera relative to the handle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of a rotation stop device;

FIG. 2 is another exploded perspective view of the device of FIG. 1;

FIG. 3 is a top view of the device of FIG. 1;

FIG. 4 is a perspective view of the device of FIG. 1;

FIG. 5 is a side view of the device of FIG. 1;

FIG. 6 is a bottom view of the device of FIG. 1;

FIG. 7 is a sectional perspective view of the device of FIG. 1;

FIG. 8 is an exploded perspective view of the device of FIG. 1;

FIG. 9A is a side view of a surgical instrument that includes a rotationstop device;

FIG. 9B is a perspective view of the instrument of FIG. 9A, shown with ahandle cover removed for clarity; and

FIG. 9C is a sectional side view of the instrument of FIG. 9A.

DETAILED DESCRIPTION

Surgical instruments with rotation stop devices and related methods aredisclosed herein, e.g., for providing limited rotation between first andsecond components of the surgical instrument in a range greater than 360degrees. Exemplary devices can have a low profile and can includevarious features to facilitate packaging of the device within a largerinstrument.

Certain exemplary embodiments will now be described to provide anoverall understanding of the principles of the structure, function,manufacture, and use of the devices and methods disclosed herein. One ormore examples of these embodiments are illustrated in the accompanyingdrawings. Those skilled in the art will understand that the devices andmethods specifically described herein and illustrated in theaccompanying drawings are non-limiting exemplary embodiments. Thefeatures illustrated or described in connection with one exemplaryembodiment may be combined with the features of other embodiments.

FIGS. 1-8 illustrate an exemplary rotation stop device 100. The device100 can allow a first component 102 to rotate relative to a secondcomponent 104 about a rotation axis A1. The device 100 can be configuredto limit the degree to which the first component 102 is allowed torotate relative to the second component 104 about the axis A1. The firstcomponent 102 can be free to rotate relative to the second component 104up to a predetermined limit. The limit can be greater than 360 degrees.The limit can be in the range of about 0 degrees to about 720 degrees.The limit can be in the range of about 360 degrees to about 720 degrees.The limit can be in the range of about 420 degrees to about 500 degrees.The limit can be greater than 720 degrees. The limit can be less than orequal to 360 degrees. As discussed further below, the rotation stopdevice 100 can be incorporated into a surgical instrument, such as anendoscope, arthroscope, surgical camera, or the like, to limit rotationbetween components of the surgical instrument.

The first component 102 can include a threaded shaft 106. The threadedshaft 106 can extend along the rotation axis A1 between a free end 108and a supported end 110. A nut 112 can be mated to the shaft 106. Forexample, the nut 112 can include an internally threaded opening 114 thatis threaded onto the exterior thread of the shaft 106. While a threadedengagement is shown, it will be appreciated that the nut 112 can bemated to the shaft 106 in other ways. For example, the nut can include apin that projects into the opening of the nut. The pin can be receivedwithin a helical groove in the exterior surface of the shaft to mate thenut to the shaft.

The second component 104 can include features for preventing rotation ofthe nut 112 relative to the second component 104 about the axis A1,while allowing the nut to translate relative to the second componentalong the axis A1. For example, the second component 104 can include acavity 116 configured to receive the nut 112 therein. The cavity 116 canbe defined by a sidewall 118. At least a portion of the sidewall 118 andat least a portion of the nut 112 can be planar or non-cylindrical andcan be configured to bear against one another to prevent relativerotation between the nut and the second component 104. The cavity 116can have a height H1 that is greater than a height H2 of the nut 112,such that the nut is capable of traveling within the cavity along theaxis A1. The threaded shaft 106 can have a height H3 that substantiallymatches or is slightly less than the height H1 of the cavity 116. Thethreaded shaft 106 can have a height H3 that is greater than the heightH2 of the nut 112.

While a cavity 116 is shown, it will be appreciated that other featuresfor preventing rotation of the nut 112 relative to the second component104 about the axis A1, while allowing the nut to translate relative tothe second component along the axis A1, can be used instead or inaddition. For example, the second component 104 can include a pinprotruding therefrom that is laterally offset from the rotation axis A1.The pin can be slidably received within a hole formed in the nut 112. Asanother example, the second component 104 can include one or more planarwalls that contact corresponding planar outer surface portions of thenut 112.

The device 100 can include features for retaining the first component102 to the second component 104, while allowing rotation therebetween.For example, the second component 104 can include one or more springtabs 120 projecting therefrom. The spring tabs 120 can be configured tosnap-fit into a throughhole 122 formed in the first component 102. Eachspring tab 120 can include a detent 124 that engages a groove or surfaceof the first component 102 to resist or prevent separation of the firstcomponent from the second component 104, while allowing the firstcomponent to rotate relative to the second component. When mated, thefirst component 102 can contact the upper surface of the sidewall 118 ofthe cavity 116, thereby forming an enclosed space in which the nut 112is non-rotatably captured. The first component 102 and the secondcomponent 104 can be configured to remain at a fixed distance from oneanother along the axis A1 as the first and second components are rotatedthrough a range of permitted rotation. While spring tabs 120 are shown,it will be appreciated that various other retention features can be usedinstead or in addition. In some embodiments, retention features can beomitted and features of an instrument or system in which the device 100is packaged can be relied upon to maintain the first and secondcomponents 102, 104 at a fixed distance along the axis A1.

The device 100 can be assembled by threading the nut 112 onto the shaft106 of the first component 102 and then inserting the shaft and the nutinto the cavity 116 of the second component 104. During assembly, thespring tabs 120 of the second component 104 can pass through thethroughhole 122 in the first component 102 and snap into place to lockthe components together.

In use, the nut 112 can interact with the first and second components102, 104 to limit relative rotation therebetween about the axis A1. Asthe first component 102 is rotated relative to the second component 104in a first direction about the axis A1, the shaft 106 can be advanceddownwards within the nut 112, causing the nut to travel upwards withinthe cavity 116. Rotation can continue until the nut 112 contacts anupper stop, e.g., the underside 126 of the first component 102. Sincethe nut 112 is constrained from rotation relative to the secondcomponent 104, further relative rotation between the first and secondcomponents in the first direction is prevented, thereby forming a firstrotation limit. As the first component 102 is rotated relative to thesecond component 104 in a second, opposite direction about the axis A1,the shaft 106 can be retracted upwards within the nut 112, causing thenut to travel downwards within the cavity 116. Rotation can continueuntil the nut 112 contacts a lower stop, e.g., the upper side 128 of thesecond component 104 or a floor of the cavity 116. Since the nut 112 isconstrained from rotation relative to the second component 104 and thesecond component is retained to the first component 102, furtherrelative rotation between the first and second components in the seconddirection is prevented, thereby forming a second rotation limit. It willthus be appreciated that the device 100 can limit relative rotation ofthe first and second components 102, 104 about the axis A1 to a rangedefined by the first and second rotation limits. The geometries of thevarious components of the device 100 can be selected to achieve adesired range of permitted rotation. For example, the height H2 of thenut 112 can be increased to reduce the range of permitted rotation orcan be decreased to extend the range of permitted rotation. As anotherexample, the height H3 of the shaft 106 can be increased to increase therange of permitted rotation or can be decreased to reduce the range ofpermitted rotation. Other parameters can be adjusted instead or inaddition, including the height of the sidewall 118, the pitch and/orlead of the threads on the shaft 106 and the nut 112, and so forth.

The device 100 can include a sensor 130 for detecting the degree ofrotation between the first and second components 102, 104. The sensor130 output can be received by a controller, processor, or circuit andused to control a system or instrument of which the device 100 is acomponent part. For example, the detected degree of rotation of asurgical instrument can be used to inform a surgical navigation systemor surgical robot as to the position or orientation of the instrument.As another example, the detected degree of rotation of a visualizationor camera instrument can be used to adjust the display of imagescaptured by the camera, e.g., by rotating or otherwise correcting thedisplayed image on a screen in accordance with the rotation detected bythe sensor 130. Exemplary sensors 130 can include potentiometers, Halleffect sensors, optical encoders, and the like.

The device 100 can include a throughhole 122 formed therein. Thethroughhole 122 can extend completely through the device 100, e.g.,through the first component 102, through the shaft 106, through the nut112, and through the second component 104, or can extend only partiallythrough the device. The throughhole 122 can be coaxial with the rotationaxis A1, can be offset therefrom, or can be obliquely angled relativethereto. The throughhole 122 can receive the spring tabs 120 discussedabove to mate the first component 102 to the second component 104.Alternatively, or in addition, the throughhole 122 can receive at leasta portion of another component of a system or instrument of which thedevice 100 is a component part. For example, the throughhole 122 canreceive a knob or shaft of a potentiometer therein. This can allow thepotentiometer to be positioned closer to the device 100 than wouldotherwise be possible, providing a reduced footprint and more efficientpackaging of the device 100 within a larger system or instrument. Thethroughhole 122 can also be used to allow connections between parts, toroute wires or optical fibers, and so forth.

The device 100 can have a low-profile, which can facilitate packaging ofthe device within a larger instrument or system. The distance H4 betweenstop surfaces 126, 128 of the device 100 can be made as small aspossible. For example, the distance H4 can be less than about 20 mm,less than about 10 mm, less than about 9 mm, less than about 7 mm,and/or less than about 5 mm.

FIGS. 9A-9C illustrate an exemplary instrument 10 that includes arotation stop device 200 of the type described herein. The device 200can include any of the features of the device 100 described above. Theinstrument 10 can be a surgical instrument, such as a surgical camerasystem, optical system, endoscope, arthroscope, or the like. Theinstrument 10 can include a proximal handle 204, which can include ahousing, and a forward knob 202. The knob 202 can be rotatable relativeto the handle 204 about an axis A2. Rotation of the knob 202 relative tothe handle 204 about the axis A2 can be effective to rotate a distalshaft 238 of the instrument, e.g., to reposition a camera or endeffector 240 within a surgical site. The rotation stop device 200 can beconfigured to limit rotation between the knob 202 and the handle 204. Inparticular, the knob 202 can serve as the “first component” of thedevice 200, including a threaded shaft 206 that extends along the axisA2. The knob 202 can be a monolithic component including the shaft 206or, as shown, the shaft can be a separate component 202A attached to themain portion 202B of the knob 202. The handle 204 can serve as the“second component” of the device 200, including a cavity 216 in which anut 212 is captured such that the nut can translate along the axis A2but is constrained from rotating relative to the housing about the axisA2. The handle 204 and the knob 202 can be maintained at a fixeddistance relative to one another along the axis A2, for example byengagement between a journal or protrusion 232 of the housing and agroove 234 of the knob. The shaft 206 can be threaded into theconstrained nut 212 to allow the device 200 to limit rotation asdescribed above.

The shaft 206 can be coupled to or formed integrally with the shaft 236of a potentiometer 230. Accordingly, rotation of the knob 202 and, byextension, the shaft 206, can be effective to rotate the potentiometershaft 236 to change an electric potential across the potentiometer 230.The electric potential, or changes thereto, can be sensed to determinethe degree of rotation of the knob 202 relative to the handle 204. Inthe case of a camera instrument, the sensed degree of rotation can beused to rotate or otherwise correct an electronic display of imagescaptured by the camera system by an amount equal to, proportional to,commensurate with, or otherwise based on the sensed degree of rotation.The rotation stop device 200 can be effective to limit rotation of thepotentiometer shaft 236 at an angle greater than 360 degrees.

As shown in FIG. 9C, the instrument 10 can include one or more elongatemembers that cross a rotation plane defined between the knob 202 and thehandle 204. A first end of the elongate member can be fixed to a portionof the instrument distal to the rotation plane and a second end of theelongate member can be fixed to a portion of the instrument proximal tothe rotation plane. For example, the instrument 10 can include one ormore optical fibers 242 and/or one or more electrical conductors orwires 244 that extend from a location proximal to the rotation plane(e.g., a proximal cable 246 of the instrument), across the rotationplane, and into a location distal to the rotation plane (e.g., a distalshaft 238 or camera assembly 240 of the instrument). In someembodiments, the instrument 10 can include an optical fiber 242 thatdirects light from a light source proximal to the handle 204 to alocation adjacent a distal end of the shaft 238. In some embodiments,the instrument 10 can include an electrical conductor 244 thatcommunicates digital or analog signals encoding image data captured byan image sensor disposed at or near the distal end of the shaft 238 fromthe image sensor to a controller or processor proximal to the handle204. It will be appreciated that the rotation stop device 200 can allowthe knob 202 to rotate relative to the handle 204 while limiting therotation to an amount less than that which could damage, break, orstress the fibers 242 or conductors 244.

It should be noted that any ordering of method steps expressed orimplied in the description above or in the accompanying drawings is notto be construed as limiting the disclosed methods to performing thesteps in that order. Rather, the various steps of each of the methodsdisclosed herein can be performed in any of a variety of sequences. Inaddition, as the described methods are merely exemplary embodiments,various other methods that include additional steps or include fewersteps are also within the scope of the present disclosure.

The devices disclosed herein can be constructed from any of a variety ofknown materials. Exemplary materials include those which are suitablefor use in surgical applications, including metals such as stainlesssteel, titanium, nickel, cobalt-chromium, or alloys and combinationsthereof, polymers such as PEEK, ceramics, carbon fiber, and so forth.The various components of the devices disclosed herein can be rigid orflexible. One or more components or portions of the device can be formedfrom a radiopaque material to facilitate visualization under fluoroscopyand other imaging techniques, or from a radiolucent material so as notto interfere with visualization of other structures. Exemplaryradiolucent materials include carbon fiber and high-strength polymers.

The devices and methods disclosed herein can be used inminimally-invasive surgery and/or open surgery. While the devices andmethods disclosed herein are generally described in the context ofsurgery on a human patient, it will be appreciated that the methods anddevices disclosed herein can be used in any type of surgery on a humanor animal subject, in non-surgical applications, on non-living objects,and so forth.

Although specific embodiments are described above, it should beunderstood that numerous changes may be made within the spirit and scopeof the concepts described.

1. A surgical method, comprising: inserting an instrument having acamera at a distal end thereof into a patient; rotating a first portionof the instrument relative to a second portion of the instrument toadjust a position of the camera, wherein said rotation is limited to arange greater than 360 degrees by a rotation stop; detecting arotational position of the first portion relative to the second portion;and adjusting an electronic display of images captured by the camerabased on the detected rotational position.
 2. The method of claim 1,wherein the first portion comprises a knob and the second portioncomprises a handle, the knob being rotatable relative to the handle torotate the camera relative to the handle.